WASHINGTON – Opponents of the Trump administration's effort to add a citizenship question to the 2020 census asked the Supreme Court Wednesday not to rule against them in the coming weeks so that new allegations of a political motive can be reviewed.

Lawyers for the New York Immigration Coalition have said information recovered from the files of a deceased Republican expert on redistricting shows the administration's motive was to reduce the voting power of Hispanics. That would help Republicans and hurt Democrats in congressional elections.

Administration officials have testified that they sought the citizenship question not for that reason but to protect minority voters under provisions of the Voting Rights Act.

Rather than decide the case on "an incomplete and misleading record," challengers asked the justices to send it back to a lower court for further fact-finding unless they are ready to strike down the citizenship question.

“The significance of this case cannot be overstated," said Dale Ho, direcor of the American Civil Liberties Union's Voting Rights Project. "The census happens once a decade, and there is no chance for a do-over."

The request came on the same day that President Donald Trump asserted executive privilege to keep secret documents related to adding the citizenship question, and a House panel voted to hold two Cabinet members in contempt for defying subpoenas for the documents.

Opponents of adding a question on citizenshp to the 2020 census asked the Supreme Court to delay its ruling while new information about the Trump administration's motive is investigated.(Photo: J. Scott Applewhite, AP)

Three federal judges have blocked the question from being added, based on both federal law and constitutional grounds. The case was argued at the Supreme Court in April; a decision is expected in the next two weeks.

During oral argument, it appeared the court's conservative majority would rule in the administration's favor. It's not surprising, therefore, that challengers would ask the court to delay its ruling.

At the center of the new controversy is Thomas Hofeller, who authored a study showing that allowing only U.S. citizens to vote "would clearly be a disadvantage to the Democrats" and "would be advantageous to Republicans and Non-Hispanic Whites."

To achieve that goal, Hofeller recommended to President-elect Donald Trump's transition team that the 2020 census ask about citizenship. But the Justice Department and Commerce Department ultimately claimed the question was intended to protect minority voting rights.

Justice Department officials have said the latest challenge represents an "eleventh-hour campaign to improperly derail the Supreme Court’s resolution of the government’s appeal."

"There is no smoking gun here," they told a federal district judge in New York last week, "only smoke and mirrors."

Judge Jesse Furman, who issued the first ruling against the administration, is considering the new information but does not intend to rule until later this summer – not in time to influence the Supreme Court.

Meanwhile, the Census Bureau has said it must have an answer soon in order to begin printing the 2020 questionnaire.

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